In comparison to other populations, coronary artery disease in African Americans is characterized by abnormalities of the microvessels, left ventricular hypertrophy, hypertension, higher blood levels of adrenalin, and salt sensitivity. The purpose of this study is to examine the effects of salt intake on nitric oxide release. The studies will be performed during a 3 day hospitalization using a standard method and will determine whether salt sensitive individuals have an impairment of nitric oxide release. The abnormalities could explain in part the overall worse outcome for black patients with heart disease. On the first day, the subject will eat a high salt die, and receive additional salt intravenously. On the second day, the subject will consume a low salt diet, and additional salt will be removed from the body by administering a diuretic. In the afternoon of each day, nitric oxide release will be assessed by measuring blood vessel size by ultrasound, and on the second day, by inserting a catheter into the brachial artery and injecting medications to stimulate nitric oxide release.